Permissions

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society c: 2010 Monthly Notices of the Royal Astronomical Society. Published by Oxford University Press. All rights reserved.

Conditions of Use

Author can archive pre-print (i.e., pre-refereeing)

Author can archive post-print (i.e., final draft post-refereeing)

Pre-print can only be posted prior to acceptance

Pre-print on author's personal website, employer website, free public server or pre-prints in subject area